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craftsman hydro 16hp 46inch too slow

3595 Views 14 Replies 4 Participants Last post by  Five Points
I bought a used model 917258590 and in high speed it seems really slow 6mph is the max it goes. Is that normal? It has 2 speeds real slow and slow. No apparent noise or issues. Any ideas would be appreciated.
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5 to 7 MPH is normal top speed for most garden tractors. Some have a 2 speed rearend like a JD 400 had higher road gear to move from job to job and might do 10 to 12 MPH. You mowing with it or racing. If you are racing buy a go kart it will live longer. Roger
Welcome to the site, invaderjb! :)

It sounds like from what you describe, 7mph that is, would be around the top speed of the machine. Unfotunately riding mowers are governed to slower speeds for safety reasons.

I looked up the model number and it displays the machine as a hydrostat. There could always be the possibility that a belt is slipping or something inside the transmission is not working correctly, although you would've probably noticed the latter of the two. If it were me and I felt like something just wasn't right, I would securly lift the tractor up, check belt tension and maybe replace/flush the transmission fluid as well. :cool:
Welcome to MLF invaderjb. I recognize you from MTF. glad you came over and I hope you got that posting issue taken care of. We'll be more than happy to give you a hand over here.

I agree with Austen, he's right on tract.
slow speed

sounds like 6mph is it

what is the process to change the fluid and what type is spec'd?

I thought I read somewhere these might need to be purged?

Your right about the karts, and I do cut fast with a 42 MTD 6speed but this craftsman would take me about twice the amount of time to complete the job.

My website is

Thanks guys your awesome!
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Do you have an owners manual?
The tranny is non-serviceable, however there are ways of doing it from draining it from the vent hole to removing a plate or splitting the case. I would inspect the belt first though.
too slow

no manual, where is the best place to find one? Thanks!
I put an owners manual in the reference library:

Also the tranny uses @ 2.5 qts of 20w-50 motor oil
If you do drain all the oil out you would have to purge the tranny.
thanks for the rapid responses and the manual

belt feels tight and no apparent slipage

motor sounds good not sure what rpm it should run I'll put a mychron tach
on it and see what its spinning

You could check the level of the fluid by cleaning the area around the vent tube, remove the vent tube, Be careful, the fitting is usually plastic, using a mirror and a flash light look in the hole and the fluid level should be @ 1.5" + - from the top of the hole.
In this case I would say though if the fluid was low, it wouldn't slow it down, it would make it surge or would have hesitations or just not work at all.
You may just have a SAFE er uh slow mower. :)
slow mower

I checked the throttle linkage its opening all the way .

next question adjusting the deck. There are two linkage arms that go toward the front axle, Those appear they would be set to have the deck level? One was missing so I fabed one. I'm having trouble getting the deck level and high enough to cut the small rear deck plastic wheel are all the way down and I'm still too low also with the knob adjusted in the highest postion before moving the deck shifter arm its too low. The back of the deck appears too low no matter what I do. I was thinking if those wheels are supposed to touch the ground maybe they are wore out.

I asked how to get the blades off the bolt is so tight I'm fighting the blade movement. Is there a stop or spaner wrench method to hold the blade while turning the bolts?
Page 44 of your owners manual shows a couple of adjustment locations for your deck. #11 & 12 adjust the lift on the deck. You may want to inspect these areas as well . The wheels are mainly to prevent scalping your yard and not so much as a support for the deck. They are only plastic wheels with a bolt going through them. Usually they are not even lubricated as the sand would stick in the grease. There are adjustments for the wheels but only to accommodate the actual deck height adjustment. I left you a response reference the blade removal in your other post.
Let us know how it turns out!
BTW page 22 show you the proper way to adjust and level the deck to include the front linkage arms ;)

Ok got I think the front two arms were too short .

I tried the wood block last nite guess I was in the wrong position will retry.

Thanks Five point!
Try clamping the block if you can't get it to wedge, just make sure you protect the paint on the outside with another piece of wood like a piece of thin plywood and even a rag between the wood and the deck exterior. Keep em' lookin good!
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